Clinical development of a blood biomarker using apolipoprotein-A2 isoforms for early detection of pancreatic cancer

BACKGROUND

We have previously reported apolipoprotein A2-isoforms (apoA2-is) as candidate plasma biomarkers for early-stage pancreatic cancer. The aim of this study was the clinical development of apoA2-is.

METHODS

We established a new enzyme-linked immunosorbent sandwich assay for apoA2-is under the Japanese medical device Quality Management System requirements and performed in vitro diagnostic tests with prespecified end points using 2732 plasma samples. The clinical equivalence and significance of apoA2-is were compared with CA19-9.

RESULTS

The point estimate of the area under the curve to distinguish between pancreatic cancer (n = 106) and healthy controls (n = 106) was higher for apoA2-ATQ/AT [0.879, 95% confidence interval (CI): 0.832-0.925] than for CA19-9 (0.849, 95% CI 0.793-0.905) and achieved the primary end point. The cutoff apoA2-ATQ/AT of 59.5 μg/mL was defined based on a specificity of 95% in 2000 healthy samples, and the reliability of specificities was confirmed in two independent healthy cohorts as 95.3% (n = 106, 95% CI 89.4-98.0%) and 95.8% (n = 400, 95% CI 93.3-97.3%). The sensitivities of apoA2-ATQ/AT for detecting both stage I (47.4%) and I/II (50%) pancreatic cancers were higher than those of CA19-9 (36.8% and 46.7%, respectively). The combination of apoA2-ATQ/AT (cutoff, 59.5 μg/mL) and CA19-9 (37 U/mL) increased the sensitivity for pancreatic cancer to 87.7% compared with 69.8% for CA19-9 alone. The clinical performance of apoA2-is was blindly confirmed by the National Cancer Institute Early Detection Research Network.

CONCLUSIONS

The clinical performance of ApoA2-ATQ/AT as a blood biomarker is equivalent to or better than that of CA19-9.

A case of rectal cancer complicated with segmental arterial mediolysis (SAM) safely treated with curative resection - A case report

INTRODUCTION

Recent advances in diagnostic imaging techniques have led to an increasing number of case reports of segmental arterial mediolysis (SAM). However, reports of abnormalities associated with SAM of abdominal organs, including the bowel, are limited. SAM, a rare vascular disease that causes spontaneous intra-abdominal bleeding, including shock and intestinal ischemia, has been reported to be associated with high mortality, but it has not been reported to coexist with rectal cancer.

CASE PRESENTATION

A 74 year-old male was referred to our hospital with a rectal cancer and he was admitted for further examination. Computed tomography angiography (CTA) revealed dissection and aneurysm in the celiac artery, superior mesenteric artery (SMA), and the inferior mesenteric artery were dilated, leading to a diagnosis of SAM.

CLINICAL DISCUSSION

Surgery for rectal cancer requires cutting the inferior mesenteric artery. The risk of bleeding during surgery increases when SAM is associated with the inferior mesenteric artery. The radical surgery for rectal cancer was executed without complications, including significant bleeding. This was achieved through careful management of SAM, meticulous control of blood pressure throughout the surgical procedure, and the delicate treatment of the SMA. A pathological diagnosis of the resected inferior mesenteric artery at the time of radical surgery was performed, and a definitive diagnosis of SAM was made.

CONCLUSION

We present a first known case in which high anterior resection was successfully performed for rectal cancer complicated by SAM. The relationship between cancer and SAM is unclear and further case accumulation is needed.

Laparoscopy-Assisted Restorative Proctocolectomy with Ileal Pouch-Anal Anastomosis in Middle Colic Artery Ligation Immediately before Specimen Removal

Introduction

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the surgical procedure for ulcerative colitis (UC). Intestinal ischemia may occur if the main blood vessels are ligated at an early stage of this surgery. Considering that the blood flow in the large intestine can be maintained by preserving the middle colic artery, we have used a new IPAA method: ligating the middle colic artery immediately before removal of the specimens ("M-method"). Here, we evaluated the M-method's clinical outcomes.

Methods

Between April 2009 and December 2021, 13 patients underwent a laparoscopy-assisted IPAA procedure at our institution. The conventional method was used for 6 patients, and the M-method was used for the other 7 patients. We retrospectively analyzed the cases' clinical notes.

Results

The M-method's rate of postoperative complications (Clavien-Dindo classification grade II or more) was significantly lower than that of the conventional method (14.2% vs. 83.3%). The M-method group's postoperative stay period was also significantly shorter (average 16.4 days vs. 55.5). There were significant differences in the albumin value and the ratio of the modified GPS score 1 or 2 on the 7th postoperative day between the M- and conventional methods (average 3.15 vs. 2.5, average 4/7 vs. 6/6). However, it is necessary to consider the small number of cases and the uncontrolled historical comparison.

Conclusion

Late ligation of the middle colic artery may be beneficial for patients' post-surgery recovery and can be recommended for IPAAs in UC patients.

The first case of laparoscopic surgery for cecal cancer occurring in a blind loop

Cancer occurrence in a blind loop is extremely rare. An 86-year-old Japanese woman underwent colonoscopy for tarry stools and weight loss; it revealed a bypass of the transverse colon and small intestine, cecal cancer, and a polyp. She had suffered from acute appendicitis and had undergone two surgeries at age 25: an appendectomy and then a bypass surgery between the transverse colon and the small intestine. We performed a laparoscopy-assisted ileocecal resection for the cancer and polyp in the blind loop with an end-to-side instrumental anastomosis. The pathological examination demonstrated that the cancer was medullary carcinoma (T2, N0, M0, Stage I) and the polyp was tubular adenoma. Two months have passed since the patient's discharge, and she is free of abdominal complaints. Our literature search identified 10 cases of cancer in a blind loop. Laparoscopy-assisted surgery may be possible in patients who have undergone blind-loop surgery.

Long-term oncological outcome of reduced-port laparoscopic surgery (single-incision plus one port) as a technical option for rectal cancer

BACKGROUND

The purpose of this study was to clarify the oncological safety of reduced-port laparoscopic surgery (single-incision plus one port) (RPS) for patients with rectal cancer.

METHODS

The clinicopathological data of 63 selected patients with clinical Stage I-III (T1-3 and N0-2) rectal cancer who underwent RPS of radical anterior resection between 2012 and 2017 were retrospectively analyzed. The median distance of tumor from anal verge was 11 cm. Ordinarily, a multiport platform with three channels was placed in the 3-cm umbilical incision, and another 5- or 12-mm port was placed in the right lower abdomen.

RESULTS

The median operative time, amount of intraoperative bleeding, number of harvested lymph nodes, and length of distal margin were 272 min, 10 mL, 22 nodes, and 4.0 cm, respectively, and there was one (2%) patient with involvement of the radial margin. There were eight patients (13%) who required additional ports, and one patient (2%) who converted to open surgery. Intra- and postoperative complications occurred in one (2%) and 12 patients (19%), respectively. The median length of postoperative hospital stay was 8 days. The median follow-up period was 79 months, and incisional hernia was observed in 3 (5%) patients at the platform site not the port site, and cancer recurrence occurred in four patients (6%). The 5-year relapse-free and overall survival rates were 100% and 100% in the patients with pathological Stage I disease, 94% and 100% in the patients with pathological Stage II disease, and 83% and 89% in the patients with pathological Stage III disease, respectively.

CONCLUSION

RPS in the selected patients with rectal cancer, performed by an expert laparoscopic surgeon, may be technically safe and oncologically acceptable as well as multiport laparoscopic surgery.

Ceramide synthase CERS4 gene downregulation is associated with KRAS mutation in colorectal cancer

Ceramide, the central molecule in sphingolipid synthesis, is a bioactive lipid that serves as a regulatory molecule in the anti-inflammatory responses, apoptosis, programmed necrosis, autophagy, and cell motility of cancer cells. In particular, the authors have reported differences in sphingolipid content in colorectal cancer tissues. The associations among genetic mutations, clinicopathological factors, and sphingolipid metabolism in colorectal cancer (CRC) have not been investigated. The objective of this study is to investigate the association between genes associated with sphingolipid metabolism, genetic variations in colorectal cancer (CRC), and clinicopathological factors in CRC patients. We enrolled 82 consecutive patients with stage I-IV CRC who underwent tumor resection at a single institution in 2019-2021. We measured the expression levels of genes related to sphingolipid metabolism and examined the relationships between CRC gene mutations and the clinicopathological data of each individual patient. The relationship between CRC gene mutations and expression levels of ceramide synthase (CERS), N-acylsphingosine amidohydrolase (ASAH), and alkaline ceramidase (ACER) genes involved in sphingolipid metabolism was examined CRES4 expression was significantly lower in the CRC KRAS gene mutation group (p = 0.004); vascular invasion was more common in colorectal cancer patients with high CERS4 expression (p = 0.0057). By examining the correlation between sphingolipid gene expression and clinical factors, we were able to identify cancer types in which sphingolipid metabolism is particularly relevant. CERS4 expression was significantly reduced in KRAS mutant CRC. Moreover, CRC with decreased CERS4 showed significantly more frequent venous invasion.

Development of fluorogenic substrates for colorectal tumor-related neuropeptidases for activity-based diagnosis

The M3 metalloproteases, neurolysin and THOP1, are neuropeptidases that are expressed in various tissues and metabolize neuropeptides, such as neurotensin. The biological roles of these enzymes are not well characterized, partially because the chemical tools to analyse their activities are not well developed. Here, we developed a fluorogenic substrate probe for neurolysin and thimet oligopeptidase 1 (THOP1), which enabled the analysis of enzymatic activity changes in tissue and plasma samples. In particular, the probe was useful for studying enzyme activities in a single-molecule enzyme assay platform, which can detect enzyme activity with high sensitivity. We detected the activity of neurolysin in plasma samples and revealed higher enzyme activity in the blood samples of patients with colorectal tumor. The result indicated that single-molecule neurolysin activity is a promising candidate for a blood biomarker for colorectal cancer diagnosis.

Inhibition of CXCR4 Enhances the Efficacy of Radiotherapy in Metastatic Prostate Cancer Models

Radiotherapy (RT) is a standard treatment for patients with advanced prostate cancer (PCa). Previous preclinical studies showed that SDF1α/CXCR4 axis could mediate PCa metastasis (most often to the bones) and cancer resistance to RT. We found high levels of expression for both SDF1α and its receptor CXCR4 in primary and metastatic PCa tissue samples. In vitro analyses using PCa cells revealed an important role of CXCR4 in cell invasion but not radiotolerance. Pharmacologic inhibition of CXCR4 using AMD3100 showed no efficacy in orthotopic primary and bone metastatic PCa models. However, when combined with RT, AMD3100 potentiated the effect of local single-dose RT (12 Gy) in both models. Moreover, CXCR4 inhibition also reduced lymph node metastasis from primary PCa. Notably, CXCR4 inhibition promoted the normalization of bone metastatic PCa vasculature and reduced tissue hypoxia. In conclusion, the SDF1α/CXCR4 axis is a potential therapeutic target in metastatic PCa patients treated with RT.

Prediction of tissue-of-origin of early stage cancers using serum miRNomes

BACKGROUND

Noninvasive detection of early stage cancers with accurate prediction of tumor tissue-of-origin could improve patient prognosis. Because miRNA profiles differ between organs, circulating miRNomics represent a promising method for early detection of cancers, but this has not been shown conclusively.

METHODS

A serum miRNA profile (miRNomes)-based classifier was evaluated for its ability to discriminate cancer types using advanced machine learning. The training set comprised 7931 serum samples from patients with 13 types of solid cancers and 5013 noncancer samples. The validation set consisted of 1990 cancer and 1256 noncancer samples. The contribution of each miRNA to the cancer-type classification was evaluated, and those with a high contribution were identified.

RESULTS

Cancer type was predicted with an accuracy of 0.88 (95% confidence interval [CI] = 0.87 to 0.90) in all stages and an accuracy of 0.90 (95% CI = 0.88 to 0.91) in resectable stages (stages 0-II). The F1 score for the discrimination of the 13 cancer types was 0.93. Optimal classification performance was achieved with at least 100 miRNAs that contributed the strongest to accurate prediction of cancer type. Assessment of tissue expression patterns of these miRNAs suggested that miRNAs secreted from the tumor environment could be used to establish cancer type-specific serum miRNomes.

CONCLUSIONS

This study demonstrates that large-scale serum miRNomics in combination with machine learning could lead to the development of a blood-based cancer classification system. Further investigations of the regulating mechanisms of the miRNAs that contributed strongly to accurate prediction of cancer type could pave the way for the clinical use of circulating miRNA diagnostics.

Easy preparation of a liposome-mediated protein delivery system by freeze-thawing a liposome–protein complex

Homeostasis can be achieved by adding a protein supplement; however, an appropriate vector is required to deliver the protein into the cell because of the low stability of proteins in...

Enhancement of target toxin neutralization effect in vivo by PEGylation of multifunctionalized lipid nanoparticles

Protein-protein (e.g., antibody-antigen) interactions comprise multiple weak interactions. We have previously reported that lipid nanoparticles (LNPs) bind to and neutralize target toxic peptides after multifunctionalization of the LNP surface (MF-LNPs) with amino acid derivatives that induce weak interactions; however, the MF-LNPs aggregated after target capture and showed short blood circulation times. Here we optimized polyethylene glycol (PEG)-modified MF-LNPs (PEG-MF-LNPs) to inhibit the aggregation and increase the blood circulation time. Melittin was used as a target toxin, and MF-LNPs were prepared with negatively charged, hydrophobic, and neutral amino-acid-derivative-conjugated functional lipids. In this study, MF-LNPs modified with only PEG5k (PEG5k-MF-LNPs) and with both PEG5k and PEG2k (PEGmix-MF-LNPs) were prepared, where PEG5k and PEG2k represent PEG with a molecular weight of 5000 and 2000, respectively. PEGylation of the MF-LNPs did not decrease the melittin neutralization ability of nonPEGylated MF-LNPs, as tested by hemolysis assay. The PEGmix-MF-LNPs showed better blood circulation characteristics than the PEG5k-MF-LNPs. Although the nonPEGylated MF-LNPs immediately aggregated when mixed with melittin, the PEGmix-MF-LNPs did not aggregate. The PEGmix-MF-LNPs dramatically increased the survival rate of melittin-treated mice, whereas the nonPEGylated MF-LNPs increased slightly. These results provide a fundamental strategy to improve the in vivo toxin neutralization ability of MF-LNPs.

Endoscopic Resection Before Surgery Does Not Affect the Recurrence Rate in Patients With High-Risk T1 Colorectal Cancer

INTRODUCTION

Patients with high-risk T1 colorectal cancer (CRC) after endoscopic resection (ER) should undergo surgery in view of the risk of lymph node metastasis. Although additional surgery can potentially prevent recurrence, there is a paucity of data and longitudinal studies exploring this potential. Hence, this study aimed to evaluate the prolonged influence of ER before additional surgery on recurrence in T1 CRC.

METHODS

Between January 2004 and October 2015, 162 patients who underwent secondary surgery (SS) after ER ([ER + SS] group) and 392 consecutive patients with T1 CRC who underwent primary surgery at our institution were retrospectively analyzed. Recurrence was analyzed in these 2 groups. High-risk CRC patients were histologically defined according to the Japanese Society for Cancer of the Colon and Rectum guidelines (2016) for the treatment of CRC. Data were analyzed based on clinical and histological features, including lymph node metastasis, and the number of lymph nodes evaluated.

RESULTS

The recurrence rate was comparable between the ER + SS and primary surgery groups, with no significant difference (P = 0.625, log-rank test). There was no significant difference in the recurrence in patients receiving adjuvant chemotherapy in both groups (7.4% vs 10.4%, P = 0.27). The difference in the mean number of lymph nodes dissected between both groups was also not significant (24.3 vs 25.3, P = 0.43).

DISCUSSION

There was no significant difference in recurrence rates between patients undergoing ER before surgery and those undergoing primary surgery for high-risk T1 CRC. Hence, ER may be acceptable for high-risk T1 CRC.

Usefulness of laparoscopic surgery and preoperative examinations for chronic recurrent small bowel obstruction

PURPOSE

The aim of this study was to investigate the usefulness of laparoscopic surgery for patients with postoperative abdominal symptoms, including chronic recurrent small-bowel obstruction (SBO), and preoperative examinations of barium follow-through and computed tomography (CT) to predict the postoperative outcomes of laparoscopic surgery.

METHODS

Between 2016 and 2018, 49 patients with postoperative symptoms were treated by laparoscopic surgery at our institute. The data from two preoperative examinations were available for 42 patients. The patients were divided into 4 groups: CT-positive (CP, n = 18), barium follow-through-positive (BP, n = 1), both positive (AP [all positive] n = 13), and both negative (AN [all negative], n = 10).

RESULTS

Among the 49 patients, 41 received pure laparoscopic surgery, 7 received laparoscopic-assisted surgery with mini-laparotomy, and 1 required conversion. Intra- and postoperative complications occurred in two and seven patients, respectively. Improvement of abdominal symptoms was observed in 40 patients. In terms of the medium-term outcomes, the rate of improvement of symptoms was poorer in the AN group than in the other three groups, but not to a significant degree.

CONCLUSION

Laparoscopic surgery was safe and feasible for patients with chronic recurrent abdominal symptoms, including SBO. Furthermore, in patients with negative results on both preoperative examinations, laparoscopic surgery may yield only poor improvement of symptoms.

Dual Programmed Death Receptor-1 and Vascular Endothelial Growth Factor Receptor-2 Blockade Promotes Vascular Normalization and Enhances Antitumor Immune Responses in Hepatocellular Carcinoma

BACKGROUND AND AIMS

Activation of the antitumor immune response using programmed death receptor-1 (PD-1) blockade showed benefit only in a fraction of patients with hepatocellular carcinoma (HCC). Combining PD-1 blockade with antiangiogenesis has shown promise in substantially increasing the fraction of patients with HCC who respond to treatment, but the mechanism of this interaction is unknown.

APPROACH AND RESULTS

We recapitulated these clinical outcomes using orthotopic-grafted or induced-murine models of HCC. Specific blockade of vascular endothelial receptor 2 (VEGFR-2) using a murine antibody significantly delayed primary tumor growth but failed to prolong survival, while anti-PD-1 antibody treatment alone conferred a minor survival advantage in one model. However, dual anti-PD-1/VEGFR-2 therapy significantly inhibited primary tumor growth and doubled survival in both models. Combination therapy reprogrammed the immune microenvironment by increasing cluster of differentiation 8-positive (CD8+ ) cytotoxic T cell infiltration and activation, shifting the M1/M2 ratio of tumor-associated macrophages and reducing T regulatory cell (Treg) and chemokine (C-C motif) receptor 2-positive monocyte infiltration in HCC tissue. In these models, VEGFR-2 was selectively expressed in tumor endothelial cells. Using spheroid cultures of HCC tissue, we found that PD-ligand 1 expression in HCC cells was induced in a paracrine manner upon anti-VEGFR-2 blockade in endothelial cells in part through interferon-gamma expression. Moreover, we found that VEGFR-2 blockade increased PD-1 expression in tumor-infiltrating CD4+ cells. We also found that under anti-PD-1 therapy, CD4+ cells promote normalized vessel formation in the face of antiangiogenic therapy with anti-VEGFR-2 antibody.

CONCLUSIONS

We show that dual anti-PD-1/VEGFR-2 therapy has a durable vessel fortification effect in HCC and can overcome treatment resistance to either treatment alone and increase overall survival in both anti-PD-1 therapy-resistant and anti-PD-1 therapy-responsive HCC models.

Abstract B89: Dual PD-1 and VEGFR-2 blockade induces vascular normalization and enhances antitumor immune responses in hepatocellular carcinoma

Introduction: Only a fraction of hepatocellular carcinoma (HCC) patients benefit from programmed death receptor-1 (PD-1) blockade. Combining PD-1 blockade with antiangiogenic treatments has been able to substantially increase the fraction of responsive HCC patients, but the mechanism of this interaction is unknown. We recapitulated these clinical outcomes (response vs. resistance) using orthotopic murine models of HCC. VEGFR2 blockade significantly delayed primary tumor growth but failed to prolong survival, while anti-PD-1 monotherapy conferred a minor survival. However, dual anti-PD-1/VEGFR-2 therapy significantly inhibited primary tumor growth and doubled survival in multiple models. Combination therapy reprogrammed the immune microenvironment by increasing CD8+ cytotoxic T-cell infiltration and activation, improving the ratio of anti- vs. pro-tumor-associated macrophages, and reducing T regulatory cell (Treg) infiltration in HCC tissue. Moreover, we found that VEGFR-2 blockade increased the PD-1 expression in tumor-infiltrating CD4+ cells. Under anti-PD-1 therapy, CD4+ cells promote normalized vessel formation in the face of antiangiogenic therapy.

Conclusion: We show that dual anti-PD-1/VEGFR-2 therapy has a durable vessel fortification effect in HCC and can overcome treatment resistance to either treatment alone and increase survival in both anti-PD-1 therapy resistant and responsive HCC models.

Citation Format: Meenal Datta, Kohei Shigeta, Tai Hato, Shuji Kitihara, Ivy X. Chen, Aya Matsui, Hiroto Kikuchi, Emilie Mamessier, Shuichi Aoki, Rakesh R. Ramjiawan, Hiroki Ochiai, Nabeel Bardeesy, Peigen Huang, Rakesh K. Jain, Mark Cobbold, Andrew X. Zhu, Dan G. Duda. Dual PD-1 and VEGFR-2 blockade induces vascular normalization and enhances antitumor immune responses in hepatocellular carcinoma [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B89.

An African pygmy hedgehog adenovirus 1 (AhAdV-1) outbreak in an African pygmy hedgehog (Atelerix albiventris) colony in Japan

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A novel adenovirus outbreak occurred in a colony of African pygmy hedgehogs (APHs).

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An African pygmy hedgehog adenovirus 1 (AhAdV-1) infection was confirmed in 13 APHs.

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AhAdV-1 was isolated from one APH.

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Five APHs died during the outbreak and AhAdV-1 can cause fatal pneumonia in a case.

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AhAdV-1 should be monitored as a potential cause of emerging infections in APHs.

An African pygmy hedgehog adenovirus 1 (AhAdV-1) outbreak in a colony of 24 African pygmy hedgehogs (APHs) with a case of fatal pneumonia occurred in Japan. Thirteen out of a colony of 15 APHs with respiratory symptoms were diagnosed with AhAdV-1 infection based on the detection of AhAdV-1 genome in throat/nasal swabs and further one APH was diagnosed on isolation of the virus. Five infected APHs died during the outbreak and AhAdV-1 caused severe pneumonia and death in one case. After the outbreak, persistent AhAdV-1 infection was suggested in one surviving APH. AhAdV-1 is a novel adenovirus and is suspected to be an emerging pathogen.

Short-term and midterm outcomes of single-incision laparoscopic surgery for right-sided colon cancer

INTRODUCTION

The purpose of this study was to clarify the usefulness of SILS for right-sided colon cancer by evaluating the short-term and midterm outcomes.

METHODS

Between 2012 and 2017, 65 selected patients with right-sided colon cancer underwent ileocecal resection, right hemicolectomy, or transverse colectomy; all were enrolled in the study. The same well-trained surgeon performed each procedure by using a multi-instrument access port with three channels, which was placed at the umbilicus via an approximately 3-cm skin incision.

RESULTS

The pathological disease stage distribution was stage 0, 4 cases; stage I, 23 cases; stage II, 19 cases; stage III, 17 cases; and stage IV, 2 cases. The surgical procedures performed were ileocecal resection, 23 cases; right hemicolectomy, 35 cases; and transverse colectomy, 7 cases. The median operative time and intraoperative blood loss were 216 min and 10 mL, respectively. Although 18 cases needed additional ports, none required conversion to open surgery. The median number of harvested lymph nodes was 24. No major perioperative morbidities occurred in this patient series. The median postoperative hospital stay was 7 days. The median follow-up period was 30 months, and the 3-year relapse-free and overall survival rates were 100% and 100%, respectively, in the stage 0-I cases and 89% and 96% in the stage II-III cases, respectively.

CONCLUSION

We concluded that SILS is as feasible as multiport laparoscopic surgery and a reliable surgical option in selected cases of right-sided colon cancer.

ROK study-C (Rainbow of KIBOU study-colorectum): a colorectal cancer survivor cohort study on food, nutrition, physical activity, psychosocial factors and its influences on colorectal cancer recurrence, survival and quality of life in Japan

BACKGROUND

Many studies have shown that lifestyle factors such as diet, physical activity are related to the incidence of cancer. However, there are few studies on the association between lifestyle factors and cancer prognosis. To investigate the influence of lifestyle factors and psychosocial factors on prognosis, we started a prospective study of women with breast cancer, the Rainbow of KIBOU study-Breast (ROK Study-B) in 2007. As of February 2018, more than 6300 women have been enrolled, thus making this one of the world's largest cancer patient cohort studies. Based on the know-how obtained from this study, we started another new cohort study for colorectal cancer patient (ROK Study-C).

METHODS

The ROK Study-C is a prospective observational study for colorectal cancer survivors at the National Cancer Center Hospital. Participants fill in several self-administrated questionnaires about lifestyle, psychosocial factors (including posttraumatic growth and benefit finding, support), and quality of life (QOL) 5 times in total: at diagnosis, 3 and 6 months, 1 and 5 years after surgery. CT-scans will be collected to assess body composition and obesity. We also use blood and cancer tissue from the Biobank. The primary endpoint is disease-free survival. The secondary endpoints are overall survival and health-related QOL. The planned sample size is 2000 and the follow-up period is 5 years after the last enrollment.

DISCUSSION

Recruitment began in December 2015 and the study is still ongoing. The ROK Study-C will contribute to improvements in patient prognosis and yield important evidence for colorectal cancer survivorship.

Improving Selection for Resection of Synchronous Para-Aortic Lymph Node Metastases in Colorectal Cancer

INTRODUCTION

The clinical benefit of extended lymphadenectomy for synchronous extraregional lymph node metastasis, such as para-aortic lymph node (PALN) metastasis in colorectal cancer, remains highly controversial.

AIM

To evaluate the clinical benefit of PALN dissection in colorectal cancer patients with synchronous PALN metastasis with or without multiorgan metastases.

METHODS

Thirty-six patients with pathologically positive PALN metastasis below the renal veins who underwent concurrent PALN dissection and primary colorectal cancer resection from January 1984 through September 2011 at the National Cancer Center Hospital in Tokyo, Japan, were included in this retrospective cohort study. We examined 5-year recurrence-free survival (RFS) rates in patient groups depending on the number of nodes involved (≤2 and ≥3 nodes) and on the presence or absence of other organ involvement (M1a and M1b,c categories in TNM staging).

RESULTS

The 5-year RFS rate was significantly different depending on the number of metastatic PALNs (42.1 and 0.6% for PALN ≤2 and ≥3, respectively, p = 0.01). The 5-year RFS rate was significantly better in patients in the M1a category than in patients in the M1b and M1c categories (27.6 and 0.0%, respectively, p < 0.01). Twenty-nine patients (80.6%) experienced recurrence after PALN dissection. Postoperative complications were seen in 14 (38.9%) patients.

CONCLUSION

PALN dissection below the renal veins for patients with isolated PALN metastasis with 2 or fewer involved PALNs may be effective in improving prognosis in colorectal cancer.

Shorter survival in adolescent and young adult patients, compared to adult patients, with stage IV colorectal cancer in Japan

BACKGROUND

The incidence of colorectal cancer in adolescent and young adult patients is increasing. However, survival and clinical features of young patients, especially those with stage IV disease, relative to adult patients remain unclear.

METHODS

This retrospective single-institution cohort study was conducted at a tertiary care cancer center. Subjects were 861 consecutive patients who were diagnosed with stage IV colorectal cancer at the age of 15 to 74 years and who were referred to the division of surgery or gastrointestinal oncology at the National Cancer Center Hospital from 1999 to 2013. Overall survival (OS) was investigated and clinicopathological variables were analyzed for prognostic significance.

RESULTS

Of these, 66 (8%) were adolescent and young adult patients and 795 (92%) were adult patients. Median survival time was 13.6 months in adolescent and young adult patients and 22.4 months in adult patients, and 5-year OS rates were 17.3% and 20.3%, respectively, indicating significant worse prognosis of adolescent and young adult patients (p = 0.042). However, age itself was not an independent factor associated with prognosis by multivariate analysis. When compared with adult patients, adolescent and young adult patients consisted of higher proportion of the patients who did not undergo resection of primary tumor, which was an independent factor associated with poor prognosis in multivariate analysis. In patients who did not undergo resection (n = 349), OS of adolescent and young adult patients were significantly worse (p = 0.033).

CONCLUSIONS

Prognoses were worse in adolescent and young adult patients with stage IV colorectal cancer compared to adult patients in Japan, due to a higher proportion of patients who did not undergo resection with more advanced and severe disease, but not due to age itself.

Prognostic Impact of R0 Resection and Targeted Therapy for Colorectal Cancer with Synchronous Peritoneal Metastasis

BACKGROUND

The National Comprehensive Cancer Network guidelines recommend R0 resection and targeted therapy, a combination of cytotoxic and molecular targeted agents, such as bevacizumab, cetuximab, and panitumumab, for colorectal cancer with synchronous peritoneal metastasis (M1c). While these therapeutic strategies are drawing attention, their efficacy has not been fully examined.

METHODS

The study population comprised 248 consecutive M1c patients who were treated at the National Cancer Center Hospital from 1997 to 2013. Multivariate analyses were performed to evaluate relationships between overall survival and R0 resection and targeted therapy using Cox proportional hazards regression models.

RESULTS

The 3-year overall survival (3 yOS) was 19.5%, and median survival time (MST) was 16.2 months in 248 M1c patients. R0 resection was performed in 34 patients (14%), yielding a 3-year overall survival (OS) of 48.3% and median survival time (MST) of 29.9 months. Targeted therapy was performed in 54 patients (22%) at least once during the course of treatment, yielding a 3-yr OS of 38.2% and MST of 23.9 months. After adjusting for other key clinical factors, such as the number of organs involved with metastases, performance status, primary tumor site, and extent of peritoneal metastasis, both R0 resection and targeted therapy were independent factors associated with longer OS. Targeted therapy was associated with a significantly longer OS compared with multiple cytotoxic agent therapy [hazard ratio 0.65; 95% confidence interval (0.44-0.94); p = 0.02].

CONCLUSIONS

If achievable, R0 resection is a desirable therapeutic strategy for patients with M1c colorectal cancer. Moreover, targeted therapy might be the optimal chemotherapy in this patient population.

Surgical outcomes of robot-assisted rectal cancer surgery using the da Vinci Surgical System: a multi-center pilot Phase II study

Introduction

We conducted a multi-center pilot Phase II study to examine the safety of robotic rectal cancer surgery performed using the da Vinci Surgical System during the introduction period of robotic rectal surgery at two institutes based on surgical outcomes.

Methods

This study was conducted with a prospective, multi-center, single-arm, open-label design to assess the safety and feasibility of robotic surgery for rectal cancer (da Vinci Surgical System). The primary endpoint was the rate of adverse events during and after robotic surgery. The secondary endpoint was the completion rate of robotic surgery.

Results

Between April 2014 and July 2016, 50 patients were enrolled in this study. Of these, 10 (20%) had rectosigmoid cancer, 17 (34%) had upper rectal cancer, and 23 (46%) had lower rectal cancer; six underwent high anterior resection, 32 underwent low anterior resection, 11 underwent intersphincteric resection, and one underwent abdominoperineal resection. Pathological stages were Stage 0 in 1 patient, Stage I in 28 patients, Stage II in 7 patients and Stage III in 14 patients. Pathologically complete resection was achieved in all patients. There was no intraoperative organ damage or postoperative mortality. Eight (16%) patients developed complications of all grades, of which 2 (4%) were Grade 3 or higher, including anastomotic leakage (2%) and conversion to open surgery (2%).

Conclusion

The present study demonstrates the feasibility and safety of robotic rectal cancer surgery, as reflected by low morbidity and low conversion rates, during the introduction period.

Preoperative T staging using CT colonography with multiplanar reconstruction for very low rectal cancer

Background

Preoperative T staging of lower rectal cancer is an important criterion for selecting intersphincteric resection (ISR) or abdominoperineal resection (APR) as well as selecting neoadjuvant therapy. The aim of this study was to evaluate the accuracy of preoperative T staging using CT colonography (CTC) with multiplanar reconstruction (MPR), in which with the newest workstation the images can be analyzed with a slice thickness of 0.5 mm.

Methods

Between 2011 and 2013, 45 consecutive patients with very low rectal adenocarcinoma underwent CTC with MPR. The accuracy of preoperative T staging using CTC with MPR was evaluated. The accuracy of preoperative T staging using MRI in the same patient population (34 of 45 patients) was also examined.

Results

Overall accuracy of T staging was 89% (41/45) for CTC with MPR and 71% (24/34) for MRI. CTC with MPR was particularly sensitive for pT2 tumors (82%; 14/17), whereas MRI tended to overstage pT2 tumors and its sensitivity for pT2 was 53% (8/15).

Conclusions

CTC with MPR, with an arbitrary selection, could be aligned to the tumor axis and better demonstrated tumor margins consecutively including the deepest section of the tumor. The accuracy of T2 and T3 staging using CTC with MPR seemed to surpass that of MRI, suggesting a potential role of CTC with MPR in preoperative T staging for very low rectal cancer.

Influence of eating quickly and eating until full on anthropometric gains in girls: A population-based, longitudinal study

BACKGROUND

In examining childhood overweight/obesity, there is a need to consider both eating quickly and eating until full. This longitudinal study investigated the influence of eating quickly and/or eating until full on anthropometric variables and becoming overweight/obese among Japanese schoolgirls.

METHODS

Study participants were fourth-grade schoolgirls (aged 9 or 10 years) in Ina Town, Japan. Physical examinations and a questionnaire survey were performed at baseline (fourth grade) and after 3 years (seventh grade). Height, weight, and waist circumference were measured in the physical examinations, while the data on eating quickly and eating until full were collected in the questionnaire survey. Analysis of variance and analysis of covariance were used to compare the differences in each anthropometric variable between fourth and seventh grade among groups.

RESULTS

Data on 425 non-overweight/obese schoolgirls in fourth grade were analyzed. Gains in anthropometric variables (body mass index, waist circumference, and waist-to-height ratio) from fourth to seventh grade were significantly larger in the "eating quickly and eating until full" group than in the "not eating quickly and not eating until full" group. In contrast, there were no significant differences in the gains between the "eating quickly or eating until full" group and the "not eating quickly and not eating until full" group. The proportion of overweight/obese girls in seventh grade was higher in the "eating quickly and eating until full" group than in the other groups.

CONCLUSIONS

Eating quickly and eating until full had a substantial impact on excess gains in anthropometric variables among schoolgirls, suggesting that modifying these eating behaviors may help prevent non-overweight/obese girls from the excess gains. Accordingly, school health programs need to focus on not eating quickly and/or not eating until full to prevent overweight/obesity; it is necessary to emphasize "the risk of overweight/obesity associated with these eating behaviors" in schools.

Long-Term Outcomes After R0 Resection of Synchronous Peritoneal Metastasis from Colorectal Cancer Without Cytoreductive Surgery or Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

The National Comprehensive Cancer Network (NCCN) guidelines for colon cancer recently added the following footnote regarding the therapeutic strategy for peritoneal metastases: "If R0 resection can be achieved, surgical resection of isolated peritoneal disease may be considered at experienced centers." This study investigated the efficacy of R0 resection of peritoneal metastasis from colorectal cancer without cytoreductive surgery or hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

This retrospective cohort study was conducted at a single-institution tertiary care cancer center. Among 496 consecutive M1c colorectal cancer patients, R0 resection was achieved for 94 patients (19%). The subjects were 78 consecutive patients with colorectal cancer and simultaneous peritoneal metastasis but no other distant metastases who underwent R0 resection at the National Cancer Center Hospital from 1971 to 2016 (16% of all M1c patients). Overall survival (OS) was investigated, and clinicopathologic variables were analyzed for prognostic significance.

RESULTS

No perioperative mortality was noted. The 3-year OS rate was 45%, and the 5-year OS rate was 28.7%. The median survival time was 33.4 months. Notably, 17 patients survived for more than 5 years, and 9 of these patients did not receive any chemotherapy. Multivariate analysis showed cancer location in the colon and harvesting of 12 or more lymph nodes to be independent factors associated with a better prognosis.

CONCLUSIONS

From the perspective of long-term outcomes and no perioperative mortality, R0 resection of peritoneal metastasis from colorectal cancer, without complete peritonectomy or HIPEC, appeared to be an acceptable therapeutic option for some patients with peritoneal metastasis.

Rapid weight gain during infancy and early childhood is related to higher anthropometric measurements in preadolescence

BACKGROUND

This study examined the relationship between rapid weight gain during infancy and/or early childhood and anthropometric measurements [body mass index (BMI), percent body fat (%BF), waist circumference (WC) and waist-to-height ratio (WHtR)] in preadolescence by sex.

METHODS

Subjects were fourth-grade school children (aged 9 to 10 years) from elementary schools in Ina-town, Japan, in 2010. Measurements of height, weight, %BF and WC were conducted for each subject. We obtained data on height and weight of subjects at birth, age 1.5 years and age 3 years from the Maternal and Child Health handbook. Rapid weight gain was defined as a change in weight-for-age standard deviation score greater than 0.67 from birth to age 1.5 years (infancy) or from age 1.5 to 3 years (early childhood).

RESULTS

All anthropometric variables (BMI, %BF, WC and WHtR) at age 9 to 10 years were significantly higher in the rapid weight gain during both infancy and early childhood period group than in the no rapid weight gain group, regardless of sex. When compared with the no rapid weight gain group, rapid weight gain during early childhood period had significantly higher BMI and WC in boys and BMI, %BF and WC in girls. Compared with the no rapid weight gain group, the rapid weight gain during infancy group had a significantly higher WC in boys and significantly higher BMI and WC in girls.

CONCLUSION

Rapid weight gain during both infancy and early childhood was related to higher anthropometric measurements, including WHtR, among Japanese preadolescents, regardless of sex. This study suggests that rapid weight gain during infancy and early childhood may be a risk factor for general/abdominal obesity later in life.

Comparison of the clinical results of abdominoperanal intersphincteric resection and abdominoperineal resection for lower rectal cancer

BACKGROUND

The aim of this study was to compare the oncologic results of abdominoperanal intersphincteric resection (ISR) and abdominoperineal resection (APR).

METHODS

Between 2003 and 2014, 277 consecutive patients with stage I-III low rectal cancer located within 5 cm from the anal verge underwent curative ISR and APR. A retrospective comparison of these two procedures was performed.

RESULTS

Overall, 128 patients underwent ISR and 149 underwent APR. The ISR group had earlier clinical stages and shorter distal margins (p < 0.01). The 5-year relapse-free survival rates in patients who underwent ISR/APR were 84.7/74.7% with T1-2 tumors and 51.3/67.6% with T3-4 tumors. In T3-4 tumors, the rate of local recurrence was higher in the ISR group (13.2%) than in the APR group (3.8%). The 5-year relapse-free survival rates in patients who underwent ISR/APR were 89.7/92.3% for stage I cases, 84.4/87.5% for stage II cases, and 39.8/51.8% for stage III cases. Patients with stage III tumors had high rates of distant recurrence in both groups (24.3 vs. 26.3%).

CONCLUSION

ISR is a feasible surgical procedure for T1-2 tumors. Patients with stage III tumors should be considered for adjuvant therapy to control distant recurrence regardless of the surgical procedure.

Potential impact of lateral lymph node dissection (LLND) for low rectal cancer on prognoses and local control: A comparison of 2 high-volume centers in Japan that employ different policies concerning LLND

BACKGROUND

Controversy remains around whether the addition of lateral lymph node dissection to total mesorectal excision offers benefits in terms of survival or local control to patients with low rectal cancer. This study aimed to examine the impact of lateral lymph node dissection in the treatment of low rectal cancer on prognosis and local control and to identify patients who might benefit from lateral lymph node dissection at 2 high-volume centers in Japan that employ different policies with regard to adopting lateral lymph node dissection.

METHODS

We reviewed outcomes from a total of 1,191 consecutive patients with low rectal cancer (rectal cancer distal to the peritoneal reflection) who underwent total mesorectal excision plus lateral lymph node dissection at 2 high-volume centers (the National Cancer Center and Aichi Cancer Center) in Japan. To assess the therapeutic outcomes of the respective node dissections, we applied an index calculated by multiplying the incidence by the 5-year overall survival of patients with metastasis in the respective lateral node stations. Multivariate analyses were performed to determine independent risk factors for local recurrence and prognostic factors.

RESULTS

Outcomes according to the presence or absence of lateral nodal metastases showed long-term survival with lateral dissection, even in patients with lateral nodal metastases (5-year overall survival: 53.1% at the National Cancer Center vs 45.2% at Aichi Cancer Center), while stage I to III patients with no lateral nodal metastases had very good prognoses at both centers (5-year overall survival: 81.7% at the National Cancer Center vs 81.0% at Aichi Cancer Center). According to the index of estimated benefit from lateral lymph node dissection, dissection of the distal internal iliac nodes and obturator nodes yielded the greatest therapeutic benefit in patients at both centers. Compared to patients with bilateral lateral lymph node dissection, the relative risk for local recurrence was 2.0 for those with unilateral lateral lymph node dissection.

CONCLUSION

Lateral lymph node dissection outcomes observed at the 2 high-volume centers in Japan demonstrate high reproducibility with good results in terms of prognosis. Differences in policies concerning the adoption of lateral lymph node dissection affected local recurrence rate.

[Peri-operative chemotherapy for resectable colorectal cancer liver metastases]

Approximately one-third of patients survive for 5 years following curative resection of hepatic metastases from colorectal cancer, and the proportion of hepatectomy-related death is as low as 1-2 %. These observations strongly support the view that hepatectomy seems to be the most effective therapy for treating hepatic metastases from colorectal cancer, due to the potential for long-term survival that is not possible with other treatment modalities. However, a hepatectomy alone does not always provide a complete cure. Adjuvant chemo- therapy may reduce the risk of recurrence and improve long-term survival, but administering systemic agents to the patients with resectable hepatic metastases in the clinical practice is not universal. Until recently, there has been little support for requiring peri-operative chemotherapy in patients with resectable hepatic metastases from colorectal cancer. We, there- fore, conducted a phase II/II randomized controlled trial (JCOG0603) to evaluate modified FOLFOX(mFOLFOX) as adjuvant chemotherapy for patients with curatively resected liver metastases from colorectal cancer. We eagerly await the results of this trial.

Blood flow speed of the gastric conduit assessed by indocyanine green fluorescence: New predictive evaluation of anastomotic leakage after esophagectomy

Anastomotic leakage is considered as an independent risk factor for postoperative mortality after esophagectomy, and an insufficient blood flow in the reconstructed conduit may be a risk factor of anastomotic leakage. We investigated the clinical significance of blood flow visualization by indocyanine green (ICG) fluorescence in the gastric conduit as a means of predicting the leakage of esophagogastric anastomosis after esophagectomy.Forty patients who underwent an esophagectomy with gastric conduit reconstruction were prospectively investigated. ICG fluorescence imaging of the gastric conduit was detected by a near-infrared camera system during esophagectomy and correlated with clinical parameters or surgical outcomes.In 25 patients, the flow speed of ICG fluorescence in the gastric conduit wall was simultaneous with that of the greater curvature vessels (simultaneous group), whereas in 15 patients this was slower than that of the greater curvature vessels (delayed group). The reduced speed of ICG fluorescence stream in the gastric conduit wall was associated with intraoperative blood loss (P = 0.008). Although anastomotic leakage was not found in the simultaneous group, it occurred in 7 patients of the delayed group (P < 0.001). A flow speed of ICG fluorescence in the gastric conduit wall of 1.76 cm/s or less was determined by a receiver operating characteristic (ROC) curve, identified as a significant independent predictor of anastomotic leakage after esophagectomy (P = 0.004).This preliminary study demonstrates that intraoperative evaluation of blood flow speed by ICG fluorescence in the gastric conduit wall is a useful means to predict the risk of anastomotic leakage after esophagectomy.

Recurrent Laryngeal Nerve Paralysis after Esophagectomy: Respiratory Complications and Role of Nerve Reconstruction

Recurrent laryngeal nerve paralysis (RLNP) after esophagectomy is a common complication and associated with aspiration pneumonia. In this study, we assessed the risk of RLNP and the usefulness of immediate reconstruction of recurrent laryngeal nerve (RLN) to prevent respiratory complications after esophagectomy. Seven hundred and eighty-two consecutive patients underwent an esophagectomy with three-field lymph node dissection, simultaneous gastric conduit reconstruction, and cervical anastomosis. Vocal cord function was observed using a flexible laryngoscope. Reconstruction between RLN and ipsilateral vagus nerve was performed during esophagectomy. RLNP was observed in 229 (29.3%) of the patients after esophagectomy: 198 unilateral and 31 bilateral cases. Of the 198 unilateral RLNP, vocal cord paralysis was observed predominantly on the left side (82.7%). RLNP was significantly associated with postoperative respiratory complications (P < 0.001) requiring a tracheotomy (P < 0.001) and mechanical ventilation (P < 0.001) and was also associated with esophagogastric anastomotic leakage (P = 0.015); consequently, the postoperative hospital stay was longer for patients with RLNP (P < 0.001). A longer operation time (P < 0.001) and advanced age (P = 0.038) were identified as significant independent predictors of RLNP. Resection of the RLN together with metastatic nodes was performed in 29 cases. The patients underwent RLN reconstruction (n = 11) had a significantly shorter postoperative hospital stay than those without RLN reconstruction (n = 18) (P = 0.019). In conclusion, RLNP was related to a poorer postoperative course among patients undergoing an esophagectomy. New surgical technologies are recommended for prevention of RLNP.

ADAM28 is expressed by epithelial cells in human normal tissues and protects from C1q-induced cell death

ADAM28 (disintegrin and metalloproteinase 28), which was originally reported to be lymphocyte-specific, is over-expressed by carcinoma cells and plays a key role in cell proliferation and progression in human lung and breast carcinomas. We studied ADAM28 expression in human normal tissues and examined its biological function. By using antibodies specific to ADAM28, ADAM28 was immunolocalized mainly to epithelial cells in several tissues, including epididymis, bronchus and stomach, whereas lymphocytes in lymph nodes and spleen were negligibly immunostained. RT-PCR, immunoblotting and ELISA analyses confirmed the expression in these tissues, and low or negligible expression by lymphocytes was found in the lymph node and spleen. C1q was identified as a candidate ADAM28-binding protein from a human lung cDNA library by yeast two-hybrid system, and specific binding was demonstrated by binding assays, immunoprecipitation and surface plasmon resonance. C1q treatment of normal bronchial epithelial BEAS-2B and NHBE cells, both of which showed low-level expression of ADAM28, caused apoptosis through activation of p38 and caspase-3, and cell death with autophagy through accumulation of LC3-II and autophagosomes, respectively. C1q-induced cell death was attenuated by treatment of the cells with antibodies against the C1q receptor gC1qR/p33 or cC1qR/calreticulin. Treatment of C1q with recombinant ADAM28 prior to addition to culture media reduced C1q-induced cell death, and knockdown of ADAM28 using siRNAs increased cell death. These data demonstrate that ADAM28 is expressed by epithelial cells of several normal organs, and suggest that ADAM28 plays a role in cell survival by suppression of C1q-induced cytotoxicity in bronchial epithelial cells.

Analysis of individual differences in radiosensitivity using genome editing

Current standards for radiological protection of the public have been uniformly established. However, individual differences in radiosensitivity are suggested to exist in human populations, which could be caused by nucleotide variants of DNA repair genes. In order to verify if such genetic variants are responsible for individual differences in radiosensitivity, they could be introduced into cultured human cells for evaluation. This strategy would make it possible to analyse the effect of candidate nucleotide variants on individual radiosensitivity, independent of the diverse genetic background. However, efficient gene targeting in cultured human cells is difficult due to the low frequency of homologous recombination (HR) repair. The development of artificial nucleases has enabled efficient HR-mediated genome editing to be performed in cultured human cells. A novel genome editing strategy, 'transcription activator-like effector nuclease (TALEN)-mediated two-step single base pair editing', has been developed, and this was used to introduce a nucleotide variant associated with a chromosomal instability syndrome bi-allelically into cultured human cells to demonstrate that it is the causative mutation. It is proposed that this editing technique will be useful to investigate individual radiosensitivity.

Rapid weight gain during early childhood is associated with overweight in preadolescence: a longitudinal study in Japan

BACKGROUND

The objective of this study was to examine the relationship between rapid weight gain during early childhood and overweight in preadolescence by sex.

METHOD

Study subjects were 676 boys and 620 girls in fourth grade (aged 9 or 10 years) from elementary schools in Ina-town, Japan, during 2010-2012. Height and weight of subjects at birth, age 1.5 and 3 years, were collected from the Maternal and Child Health Handbook, while values at 9-10 years were measured. Rapid weight gain was defined as a change in weight-for-age standard deviation score greater than 0.67 from birth to age 1.5 years (0-1.5 years) or from age 1.5 to 3 years (1.5-3 years).

RESULTS

After adjustment for confounding factors, compared with no rapid weight gain, rapid weight gain during 0-1.5 years and 1.5-3 years or rapid weight gain during 1.5-3 years but not during 0-1.5 years significantly increased the odds ratio (OR) for overweight at age 9-10 years in boys (OR, 6.21; 95% confidence interval [CI], 2.84-13.58 and OR, 3.31; 95% CI, 1.67-6.54, respectively) and girls (OR, 7.55; 95% CI, 2.99-19.07 and OR, 3.42; 95% CI, 1.38-8.49, respectively).

CONCLUSION

The present study suggests that rapid weight gain during early childhood was associated with being overweight in preadolescence, regardless of sex.

CXCR4 inhibition in tumor microenvironment facilitates anti-programmed death receptor-1 immunotherapy in sorafenib-treated hepatocellular carcinoma in mice

Sorafenib, a broad tyrosine kinase inhibitor, is the only approved systemic therapy for advanced hepatocellular carcinoma (HCC) but provides limited survival benefits. Recently, immunotherapy has emerged as a promising treatment strategy, but its role remains unclear in HCCs, which are associated with decreased cytotoxic CD8(+) T-lymphocyte infiltration in both murine and human tumors. Moreover, in mouse models after sorafenib treatment intratumoral hypoxia is increased and may fuel evasive resistance. Using orthotopic HCC models, we now show that increased hypoxia after sorafenib treatment promotes immunosuppression, characterized by increased intratumoral expression of the immune checkpoint inhibitor programmed death ligand-1 and accumulation of T-regulatory cells and M2-type macrophages. We also show that the recruitment of immunosuppressive cells is mediated in part by hypoxia-induced up-regulation of stromal cell-derived 1 alpha. Inhibition of the stromal cell-derived 1 alpha receptor (C-X-C receptor type 4 or CXCR4) using AMD3100 prevented the polarization toward an immunosuppressive microenvironment after sorafenib treatment, inhibited tumor growth, reduced lung metastasis, and improved survival. However, the combination of AMD3100 and sorafenib did not significantly change cytotoxic CD8(+) T-lymphocyte infiltration into HCC tumors and did not modify their activation status. In separate experiments, antibody blockade of the programmed death ligand-1 receptor programmed death receptor-1 (PD-1) showed antitumor effects in treatment-naive tumors in orthotopic (grafted and genetically engineered) models of HCC. However, anti-PD-1 antibody treatment had additional antitumor activity only when combined with sorafenib and AMD3100 and not when combined with sorafenib alone.

CONCLUSION

Anti-PD-1 treatment can boost antitumor immune responses in HCC models; when used in combination with sorafenib, anti-PD-1 immunotherapy shows efficacy only with concomitant targeting of the hypoxic and immunosuppressive microenvironment with agents such as CXCR4 inhibitors.

Development and Validation of LC-MS/MS Assay for the Quantification of Progesterone in Rat Plasma and its Application to Pharmacokinetic Studies

A sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of progesterone levels in rat plasma. Progesterone-d9 was used as an internal standard (IS). Samples were prepared using salting-out assisted liquid/liquid extraction (SALLE), and the extracts were injected directly onto the LC-MS/MS system. The chromatographic separation was achieved on a CAPCELL PAK C18 MGIII column (100 mm × 2.0 mm, i.d. 5 µm) using methanol and aqueous 0.1% formic acid solution gradient as the mobile phase with a constant flow rate of 0.45 mL/min. Electrospray ionization in the positive-ion mode was employed. Multiple reaction monitoring of the precursor to product ion pairs, from m/z 315.20 to m/z 109.10 for progesterone and from m/z 324.26 to m/z 113.07 for the IS, was used for quantification. Good linearity was observed over the concentration range of 0.05-20.00 ng/mL with a weighted (1/x(2)) linear regression. The intra- and inter-day precision (% relative standard deviation [RSD]) across 3 validation days over the entire concentration range was lower than 6.7%. Accuracy (% nominal) determined at 5 quality control concentrations was between 94.0 and 103.7%. The validation method was applied in a pharmacokinetic study evaluating progesterone levels after intramuscular or vaginal administration to ovariectomized (OVX) rats. The area under the plasma concentration-time curve (AUC) calculated after intramuscular administration was more than 4 times higher than the AUC measured following vaginal administration of a comparable dose.

Long-term outcome of patients with locally resected high- and low-risk rectal carcinoid tumors

BACKGROUND

Tumor size and lymphovascular invasion are known high-risk factors for lymph node and distant metastasis in patients with rectal carcinoid tumors. However, the optimal treatment for these tumors remains controversial.

AIM

The aim of this paper is to compare the outcome of local or radical resection between patients with high-risk (tumor size >10 mm or lymphovascular invasion) disease and those with low-risk (tumor size ≤10 mm, no lymphovascular invasion) disease.

METHODS

Patients with rectal carcinoid tumors treated between January 1990 and March 2010 were identified retrospectively and classified into low- and high-risk groups.

RESULTS

In total, 83 patients with rectal carcinoid tumors were included, 53 (64%) of whom were identified as low-risk and 30 (36%) as high-risk. Local resection was performed in 50 (60%) low-risk and 24 (29%) high-risk patients, and postoperative recurrence was observed in one (1%) of the high-risk patients who underwent local resection and one (11%) who underwent radical resection. No recurrence was observed in the low-risk group. Kaplan-Meier analysis of the patients who underwent local resection revealed that the 10-year disease-free survival rate was 100% in the low-risk group and 83.3% in the high-risk group.

CONCLUSIONS

There was no significant difference in outcome between local and radical resection.

Cetuximab-mediated ADCC activity is correlated with the cell surface expression level of EGFR but not with the KRAS/BRAF mutational status in colorectal cancer

Cetuximab, an IgG1 monoclonal antibody against the epidermal growth factor receptor (EGFR), is widely used for the treatment of metastatic colorectal cancer (mCRC). One of the mechanisms of action is considered to be antibody-dependent cell-mediated cytotoxicity (ADCC) triggered by Fcγ-R on natural killer cells. However, whether ADCC is associated with EGFR expression and/or the mutational status of EGF downstream effectors (KRAS and BRAF) in colorectal cancer (CRC) remains unclear. The aim of the present study was to verify whether ADCC activities are associated with the cell surface expression levels of EGFR and/or the mutational status of KRAS and BRAF. Five human CRC cell lines with different cell surface expression levels of EGFR and different KRAS and BRAF mutational statuses were selected to evaluate ADCC activity using peripheral blood mononuclear cells (PBMCs) from healthy human donors. Furthermore, tumor cells from resected specimens of CRC patients were used to evaluate the cell surface expression level of EGFR using immunohistochemistry and the KRAS and BRAF mutational statuses using direct sequencing, while the ADCC activity was examined using PBMCs from the same CRC patients. A strong correlation was observed between the expression levels of EGFR and the ADCC activities in the cell lines (correlation coefficient: 0.949; P=0.003). Of the 13 resected specimens, a high ADCC activity level was significantly observed in tumor cells with high expression levels of cell surface EGFR, when compared with that in the tumor cells with low expression levels (P=0.027). In both CRC cell lines and tumor cells from CRC patients, the ADCC activities were significantly associated with the cell surface expression levels of EGFR [standard partial regression coefficients: 0.911 (P=0.017) and 0.660 (P=0.018), respectively], but not with the mutational status of KRAS and BRAF [standard partial regression coefficient: -0.101 (P=0.631) and 0.160 (P=0.510), respectively]. Cetuximab-mediated ADCC activity may be correlated with the cell surface expression level of EGFR, regardless of the mutational statuses of KRAS and BRAF, in CRC.